All other applications are sending their notification without any issues, except the SMS application "Silence".
I went through all the advices from https://forums.garmin.com/apps-software/mobile-apps-web/f/garmin-connect-mobile-andriod/213877/notifications/1010196#1010196
I even reset my watch, re-installed garmin connect, re-installed Silence, but no luck ...
Note: my wife has the same issue as well